2-POP:2 seconds or 48 frames?

should a 2-POP be placed 2 seconds before the first frame of a program (so called First Frame Of Action or FFOA), or 48 frames before the FFOA?
Or should it be positioned at “the end of the countdown-sequence”…which, officially, should be a 24fps sequence, and starts 10 seconds before FFOA, and ends 2 seconds before FFOA.

In a 24fps-program 48 frames is automatically equal to 2 seconds, and then the 2-pop will be placed @ t.c. 00:59:58:00.
In a 25fps-program 48 frames is less than 2 seconds, and then the 2-pop will be placed @ t.c. 00:59:58:02.

Which one is the correct and official “2-POP” ?

Wikipedia says "2 seconds: https://en.wikipedia.org/wiki/2-pop
But a big, fellow, Amsterdam-based post-production studio says “48frames” in their deliveries-specs. (no link, because it’s in Dutch)

Thanks in advance for your view on this.
Niek/ Amsterdam.

Two seconds. Never ever heard it measured by frames.

However, if they want 48 frames give them that. It’s their specs. I think they’re “wrong”, but they probably don’t care what you or I think about it.

Always 48 frames. Never knew otherwise.
But it doesn’t matter, because if it’s different, it is still very clear to everybody.


Always 48 frames.
A standard leader is 192 frames long.

There are two (or three) types of leaders, Academy 12x16 frames and the SMPTE 10x24 frames. Both are 192 frames long.
The third type? It is the incorrect one. That’s ones that are not “legal” :slight_smile:.

For us working in PAL it would become really hazardous if we’d use a 2sec pop befor FFOA. Any project transferred to 24fps would then have a incorrect length of pop to ffoa. But if you place it 48 frames ahead of ffoa at 25fps, guess what happens at a 25-24fps conversion? Yep @24fps that pop would be at the correct place.

I added this, I hope I don’t sound like a douche, I just want to make sure it’s not a “but I have heard it’s always 2sec” discussion.
Who am I to claim to know the only truth?
No one, just a old-timer, have been mixing film and TV for a while and I have done more than “a few” optical transfers for sound to 35mm film back in the day, Dolby stereo, Dolby SRD and DTS. So yes I think I know my way around a leader.

48 frames always. It is the “rule”.

Although the above shows 2-POP is somewhat confusing (for juniors like me at least), it seems that 48frames is the standard.
48frames is what I’m gonna spec from now on and at least it’s a spec with “a history”, so there is an underlying reason to utilise it, I think.

Thanks very much all for your contribution on this.

Niek/ Amsterdam.

Just wondering why that is 10x24 frames? (in the context of the mentioned 192 frames).

Well I work in TV and have never ever bumped into a 2-pop that wasn’t at 00:59:58:00. Like, I’ve literally never seen it.

But the explanation for 48 frames sounds logical. They should call it something else, and one of you should sign up for a Wikipedia account and change the article there to clarify that it’s always 48 frames, not 2 seconds (I’m being serious).

Yep, the 2-pop entry in WiKipedia seems misleading.
Does anyone know a definitive reference for this on the internet?

Haha sorry 8x24 of course…
Its also what in some areas are called “a second” leader, each number is a second (24frames) apart. And yes it was really daft to call it a second leader. As that just adds to the confusion.

I did find a reference here: http://leaders.terburg.com/
but I’m wondering if there’s an ‘official’ recommendation somewhere?

Then, next question:
I live in Amsterdam, Netherlands, Europe.
Is there a common use in the 2-POP’s 1kHz-tone level? Is this -20dBFS per channel in North America and Asia, and -18dBFS per channel in Europe, or is this a “global” -20dBFS per channel?
What would you gentlemen suggest? Dutch video- and film-editor Job ter Burg uses -20dBFS per channel in the leaders in the post above.

Thanks, Niek/ Amsterdam.

Does he? Even though I posted that link I see no specific file format including audio on that website :confused: . Where is that please?

You’re right, I’m sorry.
The leader I downloaded and which contains a -20dBFS 1kHz-tone is not directly available anymore from Job ter Burg’s website, but from this Amsterdam based audio-post which directs to Job’s site and provides the -former- downloads on their own site:


This site is in Dutch, but the orange text contains the downloads to the leaders.
This is also the site where I got this “48frames-story” from , which I told about in my original post.

But still; what is common use in the 2-POP’s 1kHz-tone level?

Niek/ Amsterdam.

There is no actual standard for that.
Reason is that the standard for leaders was made in another time. Dbfs was not “invented” back then. You would never use a sync pop for any type of level indication.

There is just a few things that are good to think about. It’s exactly one frame length. It is cut on frame edges. No fades.
But 1kHz @-20dbfs is not wrong.

OK Thanks Niek.

Thanks for your explanation, Erik.
Although none of my colleagues nor clients ever have asked for reference tones, I created a couple of identification and reference tones in my DAW-templates. In my view (I live in Amsterdam, Netherlands, Europe) the reference for the 1kHz-tones should be @ -18dBF. That’s why I implemented a 2-POP of the same level; -18dBFS, only with the goal not to create confusion.
Is this a correct way of thinking? Or is -20 dBFS a more-global reference? What’s your advice on this? Or: what’s common use on this?

Niek/ Amsterdam

Hi Niek, if you want it to be coherent with your other reference tones then I see no issue with -18dBFS.

In my opinion since the 2-pop tone is not used to line up the level in any sense, then it probably doesn’t matter. Maybe the EBU has a recommendation on this, but I can’t find one.

Thanks for your comments on this.

Are you situated in Europe ?
Is there a particular reason why you’re using -20dB as your reference?

Thanks again.
Niek/ Amsterdam.

I’m in the same conundrum as you Niek as I’ve grappled with such considerations in the past. I’d use either. But you’d probably be best to get an opinion from Erik or Fredo on this…

In my response I was just giving my opinion. I don’t have a definitive answer. For clarity, I have updated my original response. Maybe the EBU has a recommendation on this, but I can’t find one.